Alcohol dependence and HCV: mechanisms of combined CNS injury

描述（由申请人提供）： 项目摘要 长期饮酒对大脑造成的主要后果之一是炎症增加，导致神经退行性病变，并伴有相关的认知和精神障碍。药物滥用后患者的神经精神损伤持续存在，并与较差的治疗结果相关。 HCV 还与多种肝外综合征相关，包括中枢神经系统 (CNS) 损伤和神经精神障碍。然而，目前尚不清楚这种认知和情绪障碍是否是全身性疾病、肝功能受损或中枢神经系统病毒感染的结果。需要动物模型来提供新的见解，以了解受共病酒精依赖和慢性病毒感染影响的分子机制和途径，以及导致戒酒和病毒清除后神经精神损伤持续存在的分子机制和途径。我们的总体假设是，患有 AUD 共病的 HCV 患者脑损伤的风险增加，从而导致酒精复发的风险。在人类和跨物种中，我们的目标是确定慢性病毒感染和酒精引起免疫细胞功能异常并导致持续性神经精神损伤的具体机制。提出以下具体目标： 1) 确定 HCV 和饮酒对患有 HCV 和 AUD 共病的退伍军人的外周 T 细胞反应和精神功能的影响。生物样本和精神病学数据将来自目前为患有 HCV 和共病 AUD 的退伍军人进行治疗试验而收集的样本和精神病学数据。我们将获得外周血单核细胞，并随时间对其进行评估：i) T 细胞群的表型变化，ii) 细胞因子的表面和细胞内积累，以及 iii) 对神经抗原和其他抗原的免疫反应性。血液样本将用于测量关键细胞因子和趋化因子、病毒载量和肝酶。还将使用衡量抑郁、焦虑和饮酒量的评定量表。将根据精神指标、病毒载量和酒精使用以及目标 2 的结果对免疫测定结果进行分析。 2) 研究慢性酒精暴露在调节感染淋巴细胞性脉络丛脑膜炎病毒（LCMV，克隆 13 变体）的小鼠的外周和中枢 T 细胞反应、中枢神经系统免疫病理学以及焦虑、抑郁和认知障碍的行为体征中的作用，这是一种已建立的 HCV 感染模型。人类。小鼠将长期暴露于并依赖于胃内施用的乙醇，然后静脉注射 LCMV（或媒介物）以评估共病的后果。接触乙醇后将进行行为测试，以评估焦虑、抑郁样行为和认知功能。将收集血液、脑和脾样本以：i) 测量血液乙醇浓度、肝酶、病毒滴度以及关键细胞因子和趋化因子，ii) 评估 T 细胞频率，包括 LCMV 特异性 CD8 T 细胞（利用四聚体分析；H-2Ld 限制性 NP118），iii) 计算产生关键细胞因子（例如， TNF-)，iv) 评估对神经抗原的免疫反应性，v) 评估神经炎症和神经元变性。检查酒精在调节 LCMV 感染小鼠的病毒持久性和中枢神经系统免疫病理学中的作用，将有助于更全面地了解共病 AUD 和 HCV，并可能确定未来治疗开发的目标。如果我们的假设得到支持，未来的研究将测试我们的免疫治疗策略，我们发现该策略可以减少甲基苯丙胺依赖小鼠模型的神经炎症并改善认知功能。成功治疗酒精引起的神经精神障碍的干预措施很有可能降低复发率并改善治疗结果。

DESCRIPTION (provided by applicant): PROJECT SUMMARY One of the major consequences of chronic alcohol use in brain is increased inflammation that leads to neurodegeneration with associated cognitive and psychiatric impairments. Neuropsychiatric impairments persist in patients following substance abuse and are associated with poorer treatment outcomes. HCV is also associated with a variety of extrahepatic syndromes, including central nervous system (CNS) damage and neuropsychiatric impairments. However, it is unclear whether such cognitive and mood disturbances are a function of systemic disease, damaged hepatic function, or virus infection of the CNS. Animal models are needed to provide new insights into the molecular mechanisms and pathways affected by co-morbid alcohol dependence and chronic viral infection, and also those which are responsible for the persistence of neuropsychiatric impairments following abstinence and viral clearance. Our overall hypothesis is that HCV patients with co-morbid AUDs are at increased risk of brain damage that contributes to alcohol relapse risk. In humans and across species, our goal is to identify specific mechanisms by which chronic viral infection and alcohol induce abnormalities in immune cell function and contribute to persistent neuropsychiatric impairments. The following specific aims are proposed: 1) Determine the effects of HCV and alcohol use on peripheral T cell response and psychiatric function in veterans with co-morbid HCV and AUDs. Biological specimens and psychiatric data will be derived from those currently being collected for a treatment trial in veterans with HCV and co-morbid AUDs. We will obtain peripheral blood mononuclear cells and evaluate them across time for: i) phenotypic changes in T-cell populations, ii) surface and intracellular accumulation of cytokines, and iii) immunoreactivity to neuroantigens and other antigens. Blood samples will be used to measure key cytokines and chemokines, viral load, and liver enzymes. Rating scales that measure depression, anxiety, and alcohol consumption will also be used. Results from the immunoassays will be analyzed in relation to psychiatric measures, viral load, and alcohol use, as well as in relation to the findings from Aim 2. 2) Investigate the role of chronic alcohol exposure in regulating peripheral and central T-cell responses, CNS immunopathology, and behavioral signs of anxiety, depression, and cognitive impairments in mice infected with lymphocytic choriomeningitis virus (LCMV, clone 13 variant), an established model for HCV infections in humans. Mice will be chronically exposed to and dependent on ethanol administered intragastrically followed by intravenous injection of LCMV (or vehicle) to evaluate the consequences of co-morbidity. Behavioral tests will be conducted following ethanol exposure to assess anxiety, depressive-like behavior, and cognitive function. Blood, brain, and spleen samples will be collected to: i) measure blood ethanol concentrations, liver enzymes, viral titers, and key cytokines and chemokines, ii) evaluate T cell frequencies, including LCMV-specific CD8+ T cells (utilizing tetramer analysis; H-2Ld-restricted NP118), iii) calculate the percentage of CD4+, CD8+, and antigen-specific CD8+ T cells producing key cytokines (e.g., TNF- ), iv) evaluate immunoreactivity to neuroantigens, and v) assess neuroinflammation and neuronal degeneration. Examining the role of alcohol in regulating viral persistence and CNS immunopathology in LCMV-infected mice will lead to a more comprehensive understanding of co-morbid AUDs and HCV and may identify targets for future therapeutic development. If our hypotheses are supported, future studies will test our immunotherapeutic strategy that we have found reduces neuroinflammation and improves cognitive function in mouse models of methamphetamine dependence. Interventions that successfully treat alcohol induced neuropsychiatric impairments have a high likelihood of also reducing relapse rates and improving treatment outcomes.